Introduction

Bughouse Chess, and its close relative Tandem Chess, are played around the world under a number of different names: Exchange Chess, Pass-On Chess, Double Bughouse, New England Double Bughouse Chess, Siamese Chess (for Tandem Chess), and Tandem Put-Back. In the
Encyclopedia of Chess Variants, Pritchard estimates that Bughouse was created in the 1960s. (I remember having played Bughouse in a Dutch chess club at around 1970.) The game has since became quite popular, with tournaments being heald consistantly up to the present time. There is even a Bughouse Newsletter, but I do not know the address. (Perhaps a reader can supply this information.)

We will begin with the more popular Bughouse Chess and then discuss the rule changes that distinguish the older Tandem Chess variant.

Team BPlayer 3

Team APlayer 1

Team BPlayer 4

Team APlayer 2

Pieces

Rules

The game is played by two teams of two players each. This requires that two chessboards be placed side by side with partners sitting on the same side of the table (see above). For each team, one player plays with white pieces and the other plays with black.

Each pair of contestants plays an
Orthodox Chess
game which has a special feature: All captured pieces are given to ones partner. Once received they become
reserve pieces
which can be
dropped
onto an empty square on the board to be used as ones own. This is done in lieu of a
board move.
(Compare Shogi.)

There is one restriction on
drops:
A captured Pawn may not be placed on the 1st or the 8th
rank.

A Rook dropped onto either Rook
home square
is considered not to have moved; so one may castle with such a Rook. A similar rule applies to a Pawn dropped onto the second rank: The Pawn inherits the two-step-move option along with the risk of
en passant capture.

You may not advise your partner, but you can ask him to capture a certain piece that you need: 'Partner, I really need a Knight'.

A gentleman's rule: In an unclocked game, a player may not delay his move beyond the time that it takes for his partner to make three moves. (This rule discourages the practice of perpetually delaying one's move in the hope that one's partner will capture a much needed piece. The rule is unnecessary, however, in a clocked game, as stalling in the presence of a clock is self-defeating.)

The game may be scored in either of two ways, depending on prior agreement:

The first mate or overtime (when using clocks) decides the match.

The first mate or overtime (when using clocks) does not decide the match, and play continues on the remaining board. Captives
in hand
may still be
dropped,
but there is no way to acquire new captives. Once the remaining game is completed, points are counted as follows: 1 for a win, 1/2 for a draw, and 0 for a loss. The team with the most points wins. If teams score 1-1, the match is a draw.

Note: A check by a
line piece
can be voided by dropping a captive between the checking piece and the King, whereas a check by a Knight cannot.

Clock-play rules

Bughouse is best played with clocks and with little time per player (e.g., 5 minutes). Clocks should be positioned so that all four players can see them clearly.

One may not inform one's partner that his opponent's time is up (flag has fallen).

There is no proscription on exactly when you must hand your partner the captured piece; it may be done before or after you hit the clock.

Tandem Chess rules

Rules are the same as for Bughouse Chess, except for the following ammendments:

Bughouse per e-mail

E-mail Bughouse requires only two players (North and South), as each assumes the role of a single set of partners. The game is played as follows:

South begins by moving a white piece.

North replies by moving a black piece followed by a white piece.

South replies by moving a white piece followed by a black piece.

Etc.

This type of play gives the e-mail game a kind of 'synchronous' effect which the face-to-face version lacks. This serves to makes it yet another chess variant.

Written by Hans Bodlaender
using information and text by Jay Scott
for additional information and links, and by Cristobal Joseevich Junta
for the `gentleman's rule'.
Edited by John William Brown for the occasion of Bughouse being selected Recognized Variant of the Month.
WWW page created: September 3, 1996. Last Modified: March 18, 2002.
﻿

Comments

Bughouse is an excellent 4 player variant that can be played with a different number of players, or (as a Bughouse variant) even a greater number of boards & sets than just two, if desired. Fwiw, I've seen on internet chat sites talk that Bughouse is hard for engines, as there are two boards & sets + drops, multiplying the possibilites compared to standard chess. If ever one of the two boards has a player sitting (refusing to move), however, the computer may then have an advantage if playing against a human on the remaining board (provided that person doesn't already have a big advantage).

From the wiki entry on Bughouse: "A valuation system, first suggested by FICS-player Gnejs, often applied to bughouse is pawn=1, bishop=knight=rook=2 and queen=4."

The one with 'Bughouse per e-mail' should instead be called 'Synchronous Bughouse', since this is game that can also be played without mail or email, but is also the way to play the Synchronous Bughouse game over the slow communication channel by two players only.

Here are some Bughouse variants by me:
1. Some possible turn variants (they can be played by 4 or 2 players, and it's possible to play these with GC):
a. In each turn, player must move one piece on both boards (in any order), possible to make one or two drops.
b. Player must chose one of boards to move or drop piece on it.
c. Turn order: p1 moves/drops on b1, p2 moves/drops on b1, p2 moves/drops on b2, p1 moves/drops on b2, p1 moves/drops on b1...
Turn variants, of course, have no advantage that original bughouse have: it can be solved. But even normal chess was not solved yet, and these will not be solved soon (if someone will try to solve them, of course).
2. Kings can be captured and dropped (it's still not allowed to castle trough check). Team loses when it have no kings (when it have king(s) in reserve only it also loses).
3. You gives captured pieces to opponent's teammate! In this game, there is no material advantage. Perhaps, it's better (for balance) to move black on one of boards first.
4. This variant was probably already invented before me as one of these many regional variants: pieces can be dropped only to starting squares of pieces of same kind.
5. Bughouse, combined with it's own 2-players variant Crazyhouse: after each capture, player must chose to give captured piece to teammate or leave for himself (probably, it's better to play it with shogi-like set).
6. And most unusual variant: Bughouse, combined with Alice chess! When piece moves, it appears on another board without changing sides (see Alice chess rules for details)! Of course, it's better to play this according to one of turn variants above, but it's possible to play with normal bughouse rules to: piece appears when move on corresponding board is finished, if square is occuppied, piece on that square gets captured (it's possible to capture king, and it's team loses).
In Russia this variant is commonly known as Swedish chess (i don't know why, maybe, it was brought to USSR by Swedish players). Naming is, of course, not important, with one expection: i don't like name 'Siamese chess'! Siamese chess is Makruk (Makruk, of course, also can be played in Bughouse style, as almost any other chess or checkers-like game)!
And who is inventor of Bughouse? Looks like, it's inventor is unknown. Interesting, did he knew about shogi when invented this?